MIT advances quantum magnetism

SAN FRANCISCO--Every once in a while, scientists make quantum leaps in technology. Researchers at MIT may have done just that recently when they showed off a new state of magnetism which could lead to quantum communication and storage.

Quantum communication, based on quantum entanglement, which does not rely on information transmission, would be a near instantaneous way of propagating information. The change in the state of one particle would simply change the state of another particle.

Meanwhile, quantum storage is another way to store data on a much smaller scale, allowing significantly larger amounts to be stored in the same amount of space.

The new magnetism purportedly comes from a synthetically grown crystal by the name of herbertsmithite, which acts as a quantum spin liquid. This means that miniscule quantum states can form inside the solid crystal which imitates liquid flux for magnetic orientations.

MIT physicists grew this pure crystal of herbertsmithite in their laboratory. This sample, which took 10 months to grow, is 7 mm long (just over a quarter-inch) and weighs 0.2 grams. Image: Tianheng Han.

For now, however, the work remains highly theoretical, and MIT researchers claim it may be quite a while before the fruits of the research become useful in the real-world technology space.

But this article was not about quantum communications in general, but rather about the discovery of a third type of magnetism, the quantum spin liquid (actually a crystal substance, but the magnetic particles in it behave like a liquid).
But the really big deal is that these magnetic particles can take on non-discrete quantum states. Fractional states, in other words, which is a really foreign concept in quantum mechanics so far.
http://www.sciencedaily.com/releases/2012/12/121220143745.htm

Quantum communications means communications which are based on quantum mechanics. Instead of thinking in terms of voltage and current, for instance, one approaches comms which depend on the emission of single photons, from an atom at the source to an atom at a destination.
One photon through a cavity, along with that photon's polarity, changes the state of one atom at the opposite end of that cavity. That single atom change of state can represent a zero or one bit value of information transfer. Think of the single photon exciting an electron at the destination to a higher energy level, with + or - spin.
If the atom at the end of the cavity can be retained in a given state, the scheme can also be used for data storage.
Point being, though, that photons must still trevel through the cavity (transmission channel). Which says that info transfer is still limited to the speed of light.

Dear Sylvie,
"Quantum communication, based on quantum entanglement, which does not rely on information transmission, would be a near instantaneous way of propagating information. The change in the state of one particle would simply change the state of another particle."
Please check your physics again...

from Wikipedia:
"Dr. George Frederick Herbert Smith (1872–1953), was a British mineralogist who worked for the British Museum of Natural History.[1] He discovered the mineral paratacamite in 1906. He also developed the first efficient jeweller's refractometer."